Combination planing and displacement boat hull

ABSTRACT

An improved boat or ship with a combination planing and displacement hull, fins mounted near the aft section provide increased planing area while still permitting a tapered aft of favorable prismatic ratio for when the boat or ship is in the displacement mode.

BACKGROUND OF THE INVENTION

[0001] The present invention relates generally to the hull configuration for boats or ships, more specifically to a lifting flange replacing the wide stem typically found on most planing hulls and thereby increasing speed and reducing fuel consumption when said water craft is not on plane but in a displacement mode. The boat as it comes off plane settles into the water, the water is then free to flow on the curved portion of the aft hull thereby reducing drag. The fins are not wings as found in hydrofoils. When on plane there is almost no water flow over the top side of the flange or fin. The fins do not generally follow the contour of the hull like lifting strakes or chine hulls.

[0002] Many planning watercraft are operated in a displacement or non-planing mode. When in rough seas or in no wake zones most planing hulls have very turbulent water flow at the aft when in the displacement mode, this is due to the abrupt end typically found on most planing hulls.

[0003] U.S. Pat. No. 5,404,830 fails to provide for a tapered hull at the aft section and uses retractable wings, when wings are deployed they abruptly extend into the water stream.

[0004] U.S. Pat. No. 3,881,438 has lifting hydrofoil wings which remain under the water and the vessel never gets on plane thereby reducing its potential speed.

[0005] U.S. Pat. No. 2,929,346 Makes no use of a planing hull and fins extend abruptly into the water stream.

[0006] None of the above patents, taken either singly or in combination, is seen to describe the instant invention as claimed.

BRIEF SUMMARY OF THE INVENTION

[0007] Accordingly, it is a principal object of the invention to provide a hull with both the advantages of a high speed planing hull with the low speed advantages of a tapered displacement hull.

[0008] It is another object of the invention to reduce fuel cost by reducing drag.

[0009] It is another object of the invention to minimize the effects of an overly buoyant hull which is subject to disruption from high sea states.

[0010] It is another object of the invention to minimize the pitch and roll by use of the fins or flanges.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a plan view of the boat.

[0012]FIG. 2 is a port elevation of the boat.

[0013]FIG. 3 is bow elevation of the boat.

[0014]FIG. 4 is a section view of the boat hull taken along the section line 4-4.

[0015]FIG. 5 is an aft elevation of the boat.

DETAILED DESCRIPTION OF THE INVENTION

[0016] A combination planing hull and displacement hull as shown in plan view FIG. 1. The plan view 6 shows the hull tapering back to the stem 1. At point 2 the fins 5 start and extend aft where the fin angles back to the main hull 3. The hull continues to taper back and a new fin 7 extends back to the stem. The jog or multiple fins 5 and 7 reduces the surface drag and provides a break for the water to separate from the boat. The stem wall 1 is sloped for the installation of a stern drive and is only wide enough for the installation of the engine and components improving the prismatic ratio, other drives systems reducing the blunt end are also anticipated. The preferred embodiment of this boat is made from marine grade aluminum.

[0017]FIG. 2 shows the Portside Elevation, the fins 5 and 7 can be seen here staggered vertically maintaining the optimum angle of attack on the water.

[0018]FIG. 3 shows the Bow Elevation of boat or ship 6

[0019]FIG. 4 shows section 4-4. Plates/fins can be seen here extending from the aft portion of the Hull 9.

[0020]FIG. 5 shows the Aft Elevation with a stem drive configuration 8.

[0021] It is understood that the present invention is not limited to the preferred embodiments described above, but encompasses any and all embodiments within the scope of the following claims. 

What is claimed is:
 1. A boat or ship with a tapered displacement type hull with a plurality of fins extending near horizontally from the port and starboard aft portion of the hull thereby improving the prismatic ratio and extending the useful area used for planing the boat or ship.
 2. A boat or ship according to claim 1 wherein the fins are staggered in elevation. 